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Loganin
Loganin is one of the best-known of the iridoid glycosides. It is named for the Loganiaceae, having first been isolated from the seeds of a member of that plant family, namely those of '' Strychnos nux-vomica''. It also occurs in '' Alstonia boonei'' (Apocynaceae), a medicinal tree of West Africa and in the medicinal/ entheogenic shrub Desfontainia spinosa ( Columelliaceae) native to Central America and South America. Biosynthesis Loganin is formed from loganic acid by the enzyme loganic acid O-methyltransferase (LAMT). Loganin then becomes a substrate for the enzyme secologanin synthase (SLS) to form secologanin, a secoiridoid monoterpene Monoterpenes are a class of terpenes that consist of two isoprene units and have the molecular formula C10H16. Monoterpenes may be linear (acyclic) or contain rings (monocyclic and bicyclic). Modified terpenes, such as those containing oxygen func ... found as part of ipecac and terpene indole alkaloids. References {{reflist Iridoid g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secologanin Synthase
In enzymology, a secologanin synthase (, was wrongly classified as in the past) is an enzyme that catalyzes the chemical reaction :loganin + NADPH + H+ + O2 \rightleftharpoons secologanin + NADP+ + 2 H2O The 4 substrates of this enzyme are loganin, NADPH Nicotinamide adenine dinucleotide phosphate, abbreviated NADP or, in older notation, TPN (triphosphopyridine nucleotide), is a cofactor used in anabolic reactions, such as the Calvin cycle and lipid and nucleic acid syntheses, which require NAD ..., H+, and O2, whereas its 3 products are secologanin, NADP+, and H2O. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-CH group of donor with oxygen as acceptor. The systematic name of this enzyme class is loganin:oxygen oxidoreductase (ring-cleaving). This enzyme participates in indole and ipecac alkaloid biosynthesis. References * * * EC 1.14.19 NADPH-dependent enzymes Enzymes of unknown structure {{1.3-en ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indole Alkaloid
Indole alkaloids are a class of alkaloids containing a structural moiety of indole; many indole alkaloids also include isoprene groups and are thus called terpene indole or secologanin tryptamine alkaloids. Containing more than 4100 known different compounds, it is one of the largest classes of alkaloids. Many of them possess significant physiological activity and some of them are used in medicine. The amino acid tryptophan is the biochemical precursor of indole alkaloids. History The action of some indole alkaloids has been known for ages. Aztecs used the psilocybin mushrooms which contain alkaloids psilocybin and psilocin. The flowering plant ''Rauvolfia serpentina'' which contains reserpine was a common medicine in India around 1000 BC. Africans used the roots of the perennial rainforest shrub Iboga, which contain ibogaine, as a stimulant. An infusion of Calabar bean seeds was given to people accused of crime in Nigeria: its rejection by stomach was regarded as a sign of i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desfontainia Spinosa
''Desfontainia'' is a genus of flowering plants in the family Columelliaceae, though it was placed formerly in Loganiaceae, Potaliaceae (later subsumed in Gentianaceae), or a family of its own, Desfontainiaceae. The genus was named for the French botanist, René Louiche Desfontaines. It is hardy to , and requires winter protection in areas with significant frosts. Species Species in the genus include: # '' Desfontainia fulgens'' D.Don - Chile, Argentina (Neuquén, Río Negro) # '' Desfontainia spinosa'' Ruiz & Pav. - from Costa Rica to Chile + Argentina # '' Desfontainia splendens'' Humb. & Bonpl. - from S Mexico to Bolivia The best known species, ''D. spinosa'' ('Chilean holly'), is a native of rainforests and mountain slopes in southern Central America and South America, occurring from Costa Rica in the north to certain islands of Tierra del Fuego (shared by Chile and Argentina) in the extreme South, being present also in Panama, Colombia, Venezuela, Peru, Bolivia and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Loganate O-methyltransferase
In enzymology, a loganate O-methyltransferase () is an enzyme that catalyzes the chemical reaction :S-adenosyl-L-methionine + loganic acid \rightleftharpoons S-adenosyl-L-homocysteine + loganin Thus, the two substrates of this enzyme are S-adenosyl methionine and loganic acid (also called loganate), whereas its two products are S-adenosylhomocysteine and loganin. This enzyme belongs to the family of transferases, specifically those transferring one-carbon group methyltransferases. The systematic name A systematic name is a name given in a systematic way to one unique group, organism, object or chemical substance, out of a specific population or collection. Systematic names are usually part of a nomenclature. A semisystematic name or semitrivial ... of this enzyme class is S-adenosyl-L-methionine:loganate 11-O-methyltransferase. Other names in common use include loganate methyltransferase, and S-adenosyl-L-methionine:loganic acid methyltransferase. This enzyme participates ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Loganic Acid
Loganic acid is an iridoid. Loganic acid is synthesized from 7-deoxyloganic acid by the enzyme 7-deoxyloganic acid hydroxylase (7-DLH). It is a substrate for the enzyme loganate O-methyltransferase for the production of loganin Loganin is one of the best-known of the iridoid glycosides. It is named for the Loganiaceae, having first been isolated from the seeds of a member of that plant family, namely those of '' Strychnos nux-vomica''. It also occurs in '' Alstonia boon ....Dewick (2009) Medicinal Natural Products: A Biosynthetic Approach. References Iridoid glycosides Glucosides Carboxylic acids Cyclopentanes {{organic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Loganiaceae
The Loganiaceae are a family of flowering plants classified in order Gentianales. The family includes up to 13 genera, distributed around the world's tropics. There are not any great morphological characteristics to distinguish these taxa from others in the order Gentianales. Many members of the Loganiaceae are extremely poisonous, causing death by convulsion. Poisonous properties are largely due to alkaloids such as those found in '' Strychnos''. Glycosides are also present as loganin in ''Strychnos''.Flowering Plants of the World by consultant editor Vernon H. Heywood, 1978, Oxford University Press, Walton Street, Oxford OX2 6DP, England, Earlier treatments of the family have included up to 29 genera. Phylogenetic studies have demonstrated that this broadly defined Loganiaceae was a polyphyletic assemblage, and numerous genera have been removed from Loganiaceae to other families (sometimes in other orders), e.g., Gentianaceae, Gelsemiaceae, Plocospermataceae ''Pl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycosides
In chemistry, a glycoside is a molecule in which a sugar is bound to another functional group via a glycosidic bond. Glycosides play numerous important roles in living organisms. Many plants store chemicals in the form of inactive glycosides. These can be activated by enzyme hydrolysis, which causes the sugar part to be broken off, making the chemical available for use. Many such plant glycosides are used as medications. Several species of ''Heliconius'' butterfly are capable of incorporating these plant compounds as a form of chemical defense against predators. In animals and humans, poisons are often bound to sugar molecules as part of their elimination from the body. In formal terms, a glycoside is any molecule in which a sugar group is bonded through its anomeric carbon to another group via a glycosidic bond. Glycosides can be linked by an O- (an '' O-glycoside''), N- (a ''glycosylamine''), S-(a '' thioglycoside''), or C- (a ''C-glycoside'') glycosidic bond. According to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iridoid
Iridoids are a type of monoterpenoids in the general form of cyclopentanopyran, found in a wide variety of plants and some animals. They are biosynthetically derived from 8-oxogeranial. Iridoids are typically found in plants as glycosides, most often bound to glucose. The chemical structure is exemplified by iridomyrmecin, a defensive chemical produced by the ant genus '' Iridomyrmex'', for which iridoids are named. Structurally, they are bicyclic ''cis''-fused cyclopentane-pyrans. Cleavage of a bond in the cyclopentane ring gives rise to a subclass known as ''secoiridoids'', such as oleuropein and amarogentin. Occurrence The iridoids produced by plants act primarily as a defense against herbivores or against infection by microorganisms. The variable checkerspot butterfly also contains iridoids obtained through its diet which act as a defense against avian predators. To humans and other mammals, iridoids are often characterized by a deterrent bitter taste. Aucubin a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monoterpene
Monoterpenes are a class of terpenes that consist of two isoprene units and have the molecular formula C10H16. Monoterpenes may be linear (acyclic) or contain rings (monocyclic and bicyclic). Modified terpenes, such as those containing oxygen functionality or missing a methyl group, are called monoterpenoids. Monoterpenes and monoterpenoids are diverse. They have relevance to the pharmaceutical, cosmetic, agricultural, and food industries. Biosynthesis Monoterpenes are derived biosynthetically from units of isopentenyl pyrophosphate, which is formed from acetyl-CoA via the intermediacy of mevalonic acid in the HMG-CoA reductase pathway. An alternative, unrelated biosynthesis pathway of IPP is known in some bacterial groups and the plastids of plants, the so-called MEP-(2-methyl-D-erythritol-4-phosphate) pathway, which is initiated from C5 sugars. In both pathways, IPP is isomerized to DMAPP by the enzyme isopentenyl pyrophosphate isomerase. Geranyl pyrophosphate is the precurs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secoiridoid
Iridoids are a type of monoterpenoids in the general form of cyclopentanopyran, found in a wide variety of plants and some animals. They are biosynthetically derived from 8-oxogeranial. Iridoids are typically found in plants as glycosides, most often bound to glucose. The chemical structure is exemplified by iridomyrmecin, a defensive chemical produced by the ant genus '' Iridomyrmex'', for which iridoids are named. Structurally, they are bicyclic ''cis''-fused cyclopentane-pyrans. Cleavage of a bond in the cyclopentane ring gives rise to a subclass known as ''secoiridoids'', such as oleuropein and amarogentin. Occurrence The iridoids produced by plants act primarily as a defense against herbivores or against infection by microorganisms. The variable checkerspot butterfly also contains iridoids obtained through its diet which act as a defense against avian predators. To humans and other mammals, iridoids are often characterized by a deterrent bitter taste. Aucubin and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central America
Central America ( es, América Central or ) is a subregion of the Americas. Its boundaries are defined as bordering the United States to the north, Colombia to the south, the Caribbean Sea to the east, and the Pacific Ocean to the west. Central America consists of eight countries: Belize, Costa Rica, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, and Panama. Within Central America is the Mesoamerican biodiversity hotspot, which extends from northern Guatemala to central Panama. Due to the presence of several active geologic faults and the Central America Volcanic Arc, there is a high amount of seismic activity in the region, such as volcanic eruptions and earthquakes which has resulted in death, injury, and property damage. In the pre-Columbian era, Central America was inhabited by the indigenous peoples of Mesoamerica to the north and west and the Isthmo-Colombian peoples to the south and east. Following the Spanish expedition of Christopher Columbus' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South America
South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southern Subregion#Americas, subregion of a single continent called Americas, America. South America is bordered on the west by the Pacific Ocean and on the north and east by the Atlantic Ocean; North America and the Caribbean Sea lie to the northwest. The continent generally includes twelve sovereign states: Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Guyana, Paraguay, Peru, Suriname, Uruguay, and Venezuela; two dependent territory, dependent territories: the Falkland Islands and South Georgia and the South Sandwich Islands; and one administrative division, internal territory: French Guiana. In addition, the ABC islands (Leeward Antilles), ABC islands of the Kingdom of the Netherlands, Ascension Island (dependency of Saint Helena, Asce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
